Exploiting Rogue Signals to Attack Trust-based Cooperative Spectrum Sensing in Cognitive Radio Networks

Abstract

EXPLOITING ROGUE SIGNALS TO ATTACK TRUST-BASED COOPERATIVE SPECTRUM SENSING IN COGNITIVE RADIO NETWORKS By David Jackson A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. Virginia Commonwealth University, 2013. Major Director: Wanyu Zang, Ph.D. Assistant Professor, Department of Computer Science Cognitive radios are currently presented as the solution to the ever-increasing spectrum shortage problem. However, their increased capabilities over traditional radios introduce a new dimension of security threats. Cooperative Spectrum Sensing (CSS) has been proposed as a means to protect cognitive radio networks from the well known security threats: Primary User Emulation (PUE) and Spectrum Sensing Data Falsification (SSDF). I demonstrate a new threat to trust-based CSS protocols, called the Rogue Signal Framing (RSF) intrusion. Rogue signals can be exploited to create the illusion of malicious sensors which leads to the framing of innocent sensors and consequently, their removal from the shared spectrum sensing. Ultimately, with fewer sensors working together, the spectrum sensing is less robust for making correct spectrum access decisions. The simulation experiments illustrate the impact of RSF intrusions which, in severe cases, shows roughly 40% of sensors removed. To mitigate the RSF intrusion’s damage to the network’s trust, I introduce a new defense based on community detection from analyzing the network’s Received Signal Strength (RSS) diversity. Tests show a 95% damage reduction in terms of removed sensors from the shared spectrum sensing, thus retaining the benefits of CSS protocols.